Drilling-machine



UNITED STATES ZATENT amen.

GEORGE G. TAFT, OF WVORGESTER, MASSACHUSETTS.

DRILLING-MACl-HNE.

SPECIFICATION forming part of Letters Patent No. 257,532, dated May 9,1882.

v Application'filed J anuary 27, 1882. (No model.) I

To all whom it may concern Be it known that I, GEORGE G. TAF r, acitizen of the United States, residing at Worcester, in the county ofWorcester and State of Massachusetts, have invented a new and usefulImprovement in Drilling Machines, of which the following is aspecification.

My invention relates to that class of drilling-machines known asself-feeding and the objects of my invention are, first, to operate thefeeding mechanism directly from the revolving drill-spindle in a morecompact and advantageous manner; and, secondly, to provide anarrangement of gearing to allow the speed of the drill-spindle to bevaried as the exigencies of the work may require.

The accompanying drawings represent a drilling-machine embodying myinvention, in which- Fi'gure 1 shows a front elevation; Fig. 2, a sideelevation; Fig. 3, a detached view of the driving-gear, and Fig. 4 aview of the bentvibrating lever.

Similar letters refer to similar parts in the several views.

Properly journaled in the frame-work A A is the drill-spindle B,with theattached bevelgear B, which receives a rotary motion from the beveledgear B, attached to the sleeve 0, in whose mortised end is placed thecrank D.

Turning upon the sleeve 0 is the pinion 0, having a mortised projection,E, upon its hub to receive the end at of the crank-bar.

Upon a stud attached to the side of the frame are the intermediategears, F and F, transferring the motion of the pinion O to the gear F,attached to the beveled gear B, the intermediate gears, F and F, beingso arranged as to reduce the speed of the beveled gear B.

The crank is interchangeable, and may be fastened in either of themortises by the setscrews ea. Forordinary work I use the crank in theposition shown in Fig. 1; but by transferring the crank to theprojection E am enabled to greatly reduce the speed of the drill-spindleB, thereby increasing its power.

The drill-spindle B carries at its upper end the screw G, which,actuated by the nut G, imparts a vertical motion to the drill-spindle B,the gear B being so attached by a spline as to permit a sliding motionof the drill-spindle,ali being an ordinaryandwell-known form ofconstruction. An intermittent rotary motion is given to the nut G by thegears H H and ratchet-wheel H, which is operated by the vibrating leverI and pawl I, the lever I turning upon the stud J, attached to the frameof the machine.

The hub K of the bevel-gear B is made eccentric or of proper cam form,and as the lever I is supported by-the stud J, parallel to thedrill-spindle B, I bend the lower end of the lever, as at L, Fig. 2, andagain at right angles to the plane of its vibration, as at L, extendingit past the center of the spindle B, in order to receive the action ofthe eccentric K, against which it is pressed by the spring 0, actingagainst the lug 0, attached to the frame. The motion of the eccentric K,acting upon the bent end of the lever I, will give a forward motion tothe pawl I and impart a rotary motion to the ratchet-wheel H, actuatingthe nut G and screw G, as shown. The spring gives the reverse motion tothe lever I and pawl I.

Opposite the lug c, I place the lug c, attached to the frame and holdingthe adjusting-screw c, which may be advanced against the lever I,checking its reverse motion, and thus permitting the pawl I to pass overone or more teeth of the ratchet-Wheel H, as may be desired. I

I do not claim the use of an intermediate gear or gears for the purposeof varying the speed of the drill-shaft; nor do I claim the use of agear or pinion running loose upon the driving-shaft for the samepurpose.

\Vhat I claim as my invention, and desire to secure by Letters Patent,is-

1. The combination, with the drill-shaft B, bevel-gears B and B,sleeveO, and its attached crank-hub, of the loose pinion O, with its mortisedprojection E upon the side of its hub, the fixed intermediate gears, FF, gear F, and interchangeable crank-bar d, all arranged and constructedas described, and for the purposes set forth.

2. The combination of the spring 0, lug c,

yibrating bent lever I, pawl l, ratchet-wheel screw G, in combinationwith the ratchet H, and eccentric K on the drill-spindle, as wheel Hvibrating lever I, pawll,a11d 00- 10 described, and for the purposes setforth. centric Is on the drill-spindle, asshown, and

3. The combination of the Vibrating bent ]efor the purposes set forth.

ver I, pawl I, ratchet-wheel H, eccentric K GEO. O. TAFT.

on the (trill-spindle adjusting-screw 0, and lug Witnesses:

o", as shown, and for the purposes specified. R. B. FOWLER,

4. The drill-shaft B and the connected feeil- II. M. FOWLER.

